A software access point is used when you want your computer to act as an access point for the local wireless network. It saves you the trouble of getting a separate wireless router.

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A software access point is used when you want your computer to act as an wifi access point for the local wireless network. It saves you the trouble of getting a separate wireless router.

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= Things you need =

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== Requirements ==

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* A nl80211 compatible wireless device (e.g. ath9k)

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== Overview ==

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You will need:

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Setting up an access point comprises two main parts:

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* Setting up the '''wifi link layer''', so that wireless clients can associate to your computer's "software access point" and send/receive IP packets from/to your computer; this is what the hostapd package will do for you

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* Setting up the '''network configuration''' on you computer, so that your computer will properly relay IP packets from/to its own Internet connection from/to wireless clients.

# '''bridge''': create a network ''bridge'' on your computer (wireless clients will appear to access the same network interface and the same subnet that's used by your computer)

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INTERFACES=(lo eth0 wlan0 br0)

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# '''NAT''': with IP forwarding/masquerading and DHCP service (wireless clients will use a dedicated subnet, data from/to that subnet is NAT-ted -- similar to a normal WiFi router that's connected to your DSL or cable modem)

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in the /etc/conf.d/bridges file, uncomment the lines (change eth1 to wlan0)

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The bridge approach is more simple, but it requires that any service that's needed by your wireless clients (like, DHCP) is available on your computers external interface. That means it will not work if you have a dialup connection (e.g., via PPPoE or a 3G modem) or if you're using a cable modem that will supply exactly one IP address to you via DHCP.

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bridge_br0="eth0 wlan0"

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The NAT aproach is more versatile, as it clearly separates wifi clients from your computer and it's completely transparent to the outside world. It will work with any kind of network connection, and (if needed) you can introduce traffic policies using the usual iptables approach.

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BRIDGE_INTERFACES=(br0)

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we are ready to go, just reboot the machine and use another computer to see if you can find the "test" wireless connection.

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Of course, is possible to '''combine both things'''. For that, studying both articles would be necessary. (Example: Like having a bridge that contains both an ethernet device and the wireless device with an static ip, offering DHCP and setting NAT configured to relay the traffic to an additional network device - that can be ppp or eth)

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=== Bridge Setup ===

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See [[Bridge with netctl]] for details.

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{{note|*untested* if your computer stops at the sign of "waiting for IP address" etc, that may be it can not find a dhcp server. so you need to set up one.}}

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Note that, you '''should not''' add the wireless device (like {{ic|wlan0}}) to the bridge; hostapd will add it on its own.

Contents

Requirements

A nl80211 compatible wireless device (e.g. ath9k)

Overview

Setting up an access point comprises two main parts:

Setting up the wifi link layer, so that wireless clients can associate to your computer's "software access point" and send/receive IP packets from/to your computer; this is what the hostapd package will do for you

Setting up the network configuration on you computer, so that your computer will properly relay IP packets from/to its own Internet connection from/to wireless clients.

Wifi Link Layer

The actual Wifi link is established via the hostapd package. That package is compatible with WPA2.

Network configuration

bridge: create a network bridge on your computer (wireless clients will appear to access the same network interface and the same subnet that's used by your computer)

NAT: with IP forwarding/masquerading and DHCP service (wireless clients will use a dedicated subnet, data from/to that subnet is NAT-ted -- similar to a normal WiFi router that's connected to your DSL or cable modem)

The bridge approach is more simple, but it requires that any service that's needed by your wireless clients (like, DHCP) is available on your computers external interface. That means it will not work if you have a dialup connection (e.g., via PPPoE or a 3G modem) or if you're using a cable modem that will supply exactly one IP address to you via DHCP.

The NAT aproach is more versatile, as it clearly separates wifi clients from your computer and it's completely transparent to the outside world. It will work with any kind of network connection, and (if needed) you can introduce traffic policies using the usual iptables approach.

Of course, is possible to combine both things. For that, studying both articles would be necessary. (Example: Like having a bridge that contains both an ethernet device and the wireless device with an static ip, offering DHCP and setting NAT configured to relay the traffic to an additional network device - that can be ppp or eth)